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When to use a Content Provider
I understand that Content Providers are made to allow publicly sharing data between applications. However, I'm wondering if anyone has thoughts about making a Content Provider to use just within your own app. Would there be any advantages to doing this? Any disadvantages?
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How to increment a datetime by one day?
...a calendar day.
Proposed solution
The following solution works for Samoa and keeps the local time constant.
def add_day(today):
"""
Add a day to the current day.
This takes care of historic offset changes and DST.
Parameters
----------
today : timezone-aware datetime obj...
How to import a module given the full path?
...rom_spec(spec)
spec.loader.exec_module(foo)
foo.MyClass()
For Python 3.3 and 3.4 use:
from importlib.machinery import SourceFileLoader
foo = SourceFileLoader("module.name", "/path/to/file.py").load_module()
foo.MyClass()
(Although this has been deprecated in Python 3.4.)
For Python 2 use:
im...
Select datatype of the field in postgres
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So simple and nice! Now I can replace the current query that I found that is 310 characters (without the table name), 4 table join, not schema aware, expensive, and that gives 'int4' and others as types instead of integer. Thank you!
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When would you use delegates in C#? [closed]
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Now that we have lambda expressions and anonymous methods in C#, I use delegates much more. In C# 1, where you always had to have a separate method to implement the logic, using a delegate often didn't make sense. These days I use delegates for:
Event handler...
How to change facet labels?
I have used the following ggplot command:
20 Answers
20
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Convert Month Number to Month Name Function in SQL
... answered Oct 9 '08 at 1:03
Alexander KojevnikovAlexander Kojevnikov
16.8k55 gold badges4545 silver badges4545 bronze badges
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How to force LINQ Sum() to return 0 while source collection is empty
...his be possible in the query itself - I mean rather than storing the query and checking query.Any() ?
6 Answers
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How can I copy data from one column to another in the same table?
... This will also work if you want to transfer old value to other column and update the first one: UPDATE table SET columnA = 'new value', columnB = columnA. Like other answer says - don't forget the WHERE clause to update only what's needed.
– Carl di Ortus
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如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...s (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for your problem, or a place to start, here are some general guidelines I’ve found to work well over the ...